Biocon Ltd.: Building a Biotech Powerhouse 527- Target identificationDrugs usually act on chemicals in the body—known as targets—which are believed to be as-sociated with a disease under investigation. Avariety of techniques are used to identify andisolate a target.
Target validationesearchers analyse andompare each drug target tos counterparts based on theirssociation with a specific dis-ase and their ability to regu-te biological and chemicalompounds in the body.- Lead identificationA lead compound is one thatis believed to have the poten-tial to treat the disease. Labo-ratory scientists compareknown substances with newcompounds to determine theirlikelihood of success. Leadsare also sometimes dev
elopedas collections—known as librar-ies—of individual molecules.4. Lead optimizationIt compares the properties ofvarious lead compounds andprovides information to helpselect the compound with thegreatest potential to bedeveloped into safe andeffective medicines.Pre-clinical studiesaboratory tests documente effect of the investigationalug on animal models (invo) and on cells in a test tuben vitro).Pharmaceuticshe results of pre-clinical test-g are used to determine howest to formulate the drug fortended clinical use. Pharma-eutics consists of twohases—pharmacologicalsts to determine the effectsthe candidate drug on theody and toxicology tests toentify risks to human body.- Phase I clinical studiesDesigned to verify safety andtolerance of the drug in hu-mans, phase I studies take,typically, between 6 and 9months. A small number ofhealthy volunteers, from 20 to100, take the investigationaldrug for short periods of time.
HIBIT 8 Drug Discovery and Development Cycle OURCE:
www.ppdi.com/PPD U7.htm, referenced February 19, 2006.- Post–marketing studiesThey test a marketed drug in new age groups and patienttypes. 11. Phase IIIb/IV studiesThey expand the testing of a proven drug to broader pa-tient populations and compare the long term effectivenessand cost of the drug to other drugs available in the marketto treat the same condition.10. New Drug ApplicationFiled with the regulatory bodies for approval (the Food andDrug Administration in the US), NDAs document the safetyand efficacy of the drug providing all the information col-lected during drug development process. Obtaining ap-provals takes between 6 months and 2 years.9. Phase III clinical studiesThey provide expanded testing of the safety and effective-ness of an investigational drug usually in randomized andblinded clinical trials. The time span is between one andfour years. Phase III trials are conducted with several hun-dreds to thousands of volunteer patients suffering fromthe condition the drug is designed to treat.8. Phase II clinical studiesDesigned to determine the effectiveness and safety of thedrug in humans, they take from 6 months up to 3 years forcompletion. Testing is done on several hundred patientssuffering from the conditions that the drug is designed totreat. Phase II study also establishes the minimum andmaximum effective dosage.
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